The long range goal of this research project is to develop protocols to test the hypothesis of a probable relationship between AHH inducibility in cultured human lymphocytes, and susceptibility to head and neck cancers. Lymphocytes will be isolated from peripheral blood samples from healthy and cancer subjects (age and sex matched), and cultured in RPMI plus 10% human AB serum plus 40 ug PHA/ml (controls), or in the above medium supplemented with 1.0 ug 1-2 benzanthracene per ml. The initial cell number is adjusted to give 0.75-1.0 times 10 to 6th power T-cells per ml of complete medium. Following a 72 hour period of growth lymphocytes will be collected, the growth supernatants are saved for the assay of lymphotoxin, and cells will be collected for AHH activity. Supernatants will be tested for target cell destruction against alpha-L-cells, and specific antibody neutralization of lymphotoxin is routinely measured.